Intestinal obstruction, as the name suggests, is an obstruction of the intestinal lumen due to various reasons, secondary to which the intestinal lumen pressure increases intestinal dilatation, and the patient experiences abdominal pain, abdominal distension, nausea, vomiting, and decreased anal defecation and bowel movements. Examination as well as diagnosis of intestinal obstruction is done by abdominal CT, not colonoscopy. Abdominal CT can detect the dilated bowel and can determine the location of the bowel obstruction, the extent of the obstruction, and CT can also detect the cause of the bowel obstruction. Conservative treatment of intestinal obstruction is also reviewed by abdominal CT to find out the degree of dilatation of the bowel. Enteroscopy is a contraindication to the examination of intestinal obstruction, because the intestinal lumen is full of stool, enteroscopy can not see the intestinal lumen, and enteroscopy need oral laxative, at this time oral laxative will aggravate intestinal obstruction or even induce intestinal perforation, and need emergency surgery. Therefore, CT is the first choice for determining whether there is intestinal obstruction.